Known air-conditioning systems treat predominately outside air that is mixed with a proportion of return or recirculated air from within a building. This conditioned air is then used to meet the heating or cooling load within a particular space, such as a number of rooms on a floor or an open space area on a floor of a building.
A chilled beam is one such type of convection HVAC system designed to heat or cool buildings. Pipes carrying water are passed through a beam; i.e., a heat exchanger, suspended a short distance from the ceiling of a room. As the beam chills the air around it, the air becomes denser and falls to the floor. It is replaced by warmer air moving up from below, causing a constant flow of convection and cooling the room.
An active chilled beam, also know as an induction diffuser, utilizes ducts to push or induce air, such as recirculated or secondary air (also known as induced air), toward the unit. Known active chilled beam systems, however, are not particularly suitable for hospitals and other environments wherein recirculated or secondary air may carry bacteria, germs, and the like.
Accordingly, there is a need for an active chilled beam system that is particularly suited for use in hospital patient rooms, outpatient rooms, nurses' stations, waiting areas, and in any area of a hospital that allows recirculation, among other areas where heating, cooling and/or sterilization of recirculated air is desired.